function time_ago(time) {
switch (typeof time) {
case 'number':
break;
case 'string':
time = +new Date(time);
break;
case 'object':
if (time.constructor === Date) time = time.getTime();
break;
default:
time = +new Date();
}
var time_formats = [
[60, 'seconds', 1], // 60
[120, '1 minute ago', '1 minute from now'], // 60*2
[3600, 'minutes', 60], // 60*60, 60
[7200, '1 hour ago', '1 hour from now'], // 60*60*2
[86400, 'hours', 3600], // 60*60*24, 60*60
[172800, 'Yesterday', 'Tomorrow'], // 60*60*24*2
[604800, 'days', 86400], // 60*60*24*7, 60*60*24
[1209600, 'Last week', 'Next week'], // 60*60*24*7*4*2
[2419200, 'weeks', 604800], // 60*60*24*7*4, 60*60*24*7
[4838400, 'Last month', 'Next month'], // 60*60*24*7*4*2
[29030400, 'months', 2419200], // 60*60*24*7*4*12, 60*60*24*7*4
[58060800, 'Last year', 'Next year'], // 60*60*24*7*4*12*2
[2903040000, 'years', 29030400], // 60*60*24*7*4*12*100, 60*60*24*7*4*12
[5806080000, 'Last century', 'Next century'], // 60*60*24*7*4*12*100*2
[58060800000, 'centuries', 2903040000] // 60*60*24*7*4*12*100*20, 60*60*24*7*4*12*100
];
var seconds = (+new Date() - time) / 1000,
token = 'ago',
list_choice = 1;
if (seconds == 0) {
return 'Just now'
}
if (seconds < 0) {
seconds = Math.abs(seconds);
token = 'from now';
list_choice = 2;
}
var i = 0,
format;
while (format = time_formats[i++])
if (seconds < format[0]) {
if (typeof format[2] == 'string')
return format[list_choice];
else
return Math.floor(seconds / format[2]) + ' ' + format[1] + ' ' + token;
}
return time;
}
var aDay = 24 * 60 * 60 * 1000;
console.log(time_ago(new Date(Date.now() - aDay)));
console.log(time_ago(new Date(Date.now() - aDay * 2)));